Field of the Invention. This invention relates to switch-mode power conditioning circuits which provide regulated DC output power from an AC power source while drawing resistive, (i.e., sinusoidal), input current in applications where harmonic current generation in the utility distribution and generation system must be minimized. In particular, the invention relates to a switch-mode power conditioner which produces a transformer isolated 200 Vdc output at 450 watts from a 120 Vac (60 Hz to 400 Hz) power source while drawing resistive input current.